SSC Junior Engineer Electrical Online Exam 2018 CPWD/CWC/MES Electrical Engineering 22-01-2018 Evening

1. . Which one of the following has the ability to store energy in the form of electric charge ?

A) Super conductor
B) Resistor
C) Capacitor
D) Inductor

... Answer is C)
Capacitors

A capacitor can store electric energy when disconnected from its charging circuit, so it can be used like a temporary battery, or like other types of rechargeable energy storage system.

Capacitors are commonly used in electronic devices to maintain power supply while batteries change.

2. . Which one of the following has the least number of free electrons in it ?

A) Conductors
B) Semiconductor
C) Super conductor
D) Insulators

... Answer is D)
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3. . Watt is the S.I. unit of ........... ?

A) Current
B) Voltage
C) Power
D) Resistance

... Answer is C)
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4. Which of the following is the correct expression for the electrical power ?

A) VR
B) V/R
C) V squre /R
D) V squre*R

... Answer is C)
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5. . What will be the resistance (in ohms) of a resistor, when the current through the resistor is 2 A and the potential difference between the ends of the resistor is 40 V ?

A) 20
B) 10
C) 30
D) 40

... Answer is A)
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6. What will be the cross-sectional area (in sq. m) of an 18 m long cylindrical wire when the resistivity of the wire is 0.67 ohm-meter and the resistance of the wire is 12 ohms ?

A) 2
B) 1
C) 6
D) 3

... Answer is B)
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7. . Determine the equivalent capacitance (in µF) of the given electrical network ?

A) 24.21
B) 21.25
C) 26.64
D) 22.66

... Answer is D)
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8. Determine the separation between the plates (in mm)of a parallel plate capacitor placed in air, when the area of the plates is 0.002 sq. meter, the voltage of the battery connected to this parallel plate capacitor is 4 V and the charge stored on the plates is 16 pC ?

A) 4.4
B) 2.6
C) 5.8
D) 6.4

... Answer is A)
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9. . Determine the power (in W) delivered by the current source to the given electrical circuit ?

A) 92.5
B) 107.5
C) 104.2
D) 93.7

... Answer is B)
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10. Determine the power (in W) of lamp A and lamp B respectively for the given circuit diagram ?

A) 75.56, 33.64
B) 76.65, 38.86
C) 70.76, 35.37
D) 68.62, 38.86

... Answer is C)
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11. Which one of the following statement is TRUE ?

A) Superposition theorem is not applicable for voltage calculation
B) Superposition theorem is not applicable for power calculation
C) Superposition theorem is not applicable for bilateral elements
D) Superposition theorem is not applicable for passive elements

... Answer is B)
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12. Which one of the following is an active element in a circuit ?

A) Capacitor
B) Resistance
C) Inductor
D) Current source

... Answer is D)
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13. The closed path made by the combination of several branches of the network is called as........ ?

A) terminal
B) circuit
C) loop
D) junction

... Answer is C)
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14. Which one of the following is the statement of Ohm's law ?

A) Voltage is always equal to current
B) Voltage is inversely proportional to current
C) Current is directly proportional to the voltage
D) Current does not depend on the voltage

... Answer is C)
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15. What will be the value of current l5 (in A) for the given network ?

A) 1
B) 2
C) 3
D) 4

... Answer is B)
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16. Determine the Thevenin's equivalent resistance (in ohms) across terminals x and y for the given electrical circuit ?

A) 1.21
B) 2.32
C) 3.43
D) 4.54

... Answer is C)
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17. . What will be the voltage (in V) between points 'A' and 'B' in the given electrical circuit ?

A) 38.25
B) 36.62
C) 32.24
D) 37.32

... Answer is D)
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18. What will be the voltage (in V) at node A of the given circuit diagram ?

A) 24
B) 12
C) 10
D) 9

... Answer is D)
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19. What will be the current (in A) through 4 ohms resistor, if a source of 4 V with internal resistance of 2 ohms is connected at x-y terminals with positive terminal at x ?

A) 0.75
B) 0.24
C) 1.62
D) 1.44

... Answer is A)
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20. Find the value of current (in A) through the load resistance (RL) in the given circuit diagram ?

A) 2.2
B) 1.3
C) 2.6
D) 2.25

... Answer is B)
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21. The S.I. unit magnetic permeance is ..... ?

A) Henry
B) Tesla
C) Coulomb
D) Weber

... Answer is A)
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22. Which one of the following is the CORRECT expression of magnetic reluctance ?

A) l/H
B) B/H
C) φ/Fm
D) Fm/φ

... Answer is D)
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23. Determine the produced mmf (in Amp-turns) in a magnetic circuit if it has 60 turns and carrying a current of 0.5 A ?

A) 10
B) 20
C) 30
D) 40

... Answer is c)
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24. Magnetic flux through any closed surface is. ?

A) one
B) infinite
C) zero
D) negative

... Answer is C)
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25. . Determine the magnitude of induced EMF (in V) in a coil, if the current changes from +2 A to –2A in 0.5 seconds and the coefficient of mutual induction is 0.5 ?

A) 2
B) 4
C) 3
D) 6

... Answer is B)
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26. Determine the self-inductance (in mH) of a 4 m long air-cored solenoid, if the solenoid has a cross sectional area of 0.02 square meter and has 60 turns ?

A) 0.064
B) 0.036
C) 0.045
D) 0.023

... Answer is D)
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27. Determine the value of magnetic field (in mT) at the centre of a 20 cm long solenoid, if the solenoid has 200 turns and carrying a current of 4 A ?

A) 5
B) 8
C) 9
D) 11

... Answer is A)
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28. What will be the magnitude of magnetic field (in T) acting parallel to the rotation of the disc of diameter 20 cm when the magnitude of EMF induced between the axis of rotation and the rim of the disc is 10 V and the angular speed of rotation of disc is 20 revolutions per second ?

A) 12.8
B) 14.3
C) 15.9
D) 16.8

... Answer is C)
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29. Determine the magnetic susceptibility of a material, if the field strength of the materials is 0.8 × 105 A.m–1 and the magnitude of magnetization is 0.97 × 105 A.m–1 ?

A) 1.01
B) 1.21
C) 1.41
D) 1.61

... Answer is B)
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30. What will be the magnitude of the induced EMF (in V) in a coil area of 100 square centimeters with 200 turns, If the coil is removed from a magnetic field of 10 T acting at right angles to the coil in 1 second ?

A) 10
B) 30
C) 60
D) 20

... Answer is D)
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31. What will be the instantaneous value of the alternating voltage (in V) which is represented by v(t) = 120 sin(11t – 20)V, when the value of is 10 ?

A) 0
B) 60
C) 84.85
D) 120

... Answer is D)
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32. What is the peak value of the alternating current (in A) having RMS value of 18 A ?

A) 25.46
B) 28.3
C) 33.34
D) 35.99

... Answer is A)
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33. What will be the value of capacitive reactance (in ohms) of a circuit, if it is supplied with 25 Hz supply, if the capacitive reactance of the circuit is 30 Ohms, when it is supplied with a 100 Hz supply ?

A) 50
B) 60
C) 75
D) 120

... Answer is D)
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34. A series RLC circuit has a capacitance, inductance and resistance of 0.018 mF, 2 mH and 10 Ohms respectively. What is the resonant frequency (in kHz) of the circuit ?

A) 13.26
B) 26.52
C) 53.04
D) 79.56

... Answer is #)
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35. What is the value of current (in A) at half power of a series RLC circuit at resonance, when the maximum value of current is 20 A ?

A) 5
B) 10
C) 12.74
D) 14.14

... Answer is D)
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36. What is the value of quality factor of a series RLC circuit having capacitance of 0.01 mF, inductance of 1 mH and resistance of 75 Ohms ?

A) 0.133
B) 0.267
C) 1.333
D) 2.667

... Answer is A)
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37. Which of the following is CORRECT about series RLC circuit ?

A) Its bandwidth decreases with decrease in inductance
B) Its bandwidth decreases with decrease in resistance
C) Its bandwidth decrease with increase in resistance
D) Its bandwidth is independent of both inductance and resistance

... Answer is B)
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38. What is the number of watt-meters required to measure the power of a poly phase system containing 'n' conductors ?

A) 0
B) n – 1
C) n
D) n + 1

... Answer is B)
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39. The reading of wattmeter and ammeter is 1 kW and 10 A respectively in the three phase circuit given below. What is the value of power factor of the circuit, if the circuit is balanced ?

A) 0.5
B) 0.65
C) 0.74
D) 0.86

... Answer is D)
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40. What is the apparent power of a 3-phase star connected system having phase voltage of 254.05 V and line current of 10 A and the phase difference between the voltage and current is 45 degrees ?

A) 5.4kW
B) 5.4 kVA
C) 7.62kW
D) 7.62 kVA

... Answer is #)
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41. . Which of the following is the dimension of power ?

A) N m
B) R K
C) A S
D) M S

... Answer is A)
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42. A factory runs in 4 shifts of 6 hours each, in which it consumes 36 kW, 86kW, 50 kW and 20 kW in each shift respectively. Calculate the energy (in kWh) consumed by the factory per day ?

A) 216
B) 557
C) 1152
D) 1920

... Answer is C)
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43. In 'Two-wattmeter method' of power calculation of a 3-phase balanced star connected system, what is the power factor of the system, if one of the wattmeters shows negative reading and the other shows a positive reading ?

A) Greater than or equal 0 but less than 0.5
B) 0.5
C) Greater than 0.5 but less than equal to 1
D) Greater than 1

... Answer is A)
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44. Which of the following is NOT a feature of MI type instruments ?

A) Can be used in both AC and DC circuit
B) Moving element is a small soft iron piece
C) Uniformly divided scale
D) Low cost of instrument in comparison to moving coil instruments

... Answer is C)
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45. What is the phase shift (in degrees) between the signals, which is indicated by the Lissajous pattern given below ?

A) 0
B) 60
C) 90
D) 180

... Answer is D)
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46. Which of the following is used to measure the power in very high voltage circuits with a low rating wattmeters ?

A) Cannot be measured
B) Instrument transformer is used
C) Full wave rectifier is used
D) Few number of wattmeter transformer is used

... Answer is B)
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47. What is the smallest change in the input signal that can be detected by an instrument called ?

A) Accuracy
B) Precision
C) Resolution
D) Sensitivity

... Answer is C)
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48. Which of the following is TRUE in case of current transformers ?

A) It helps in measuring high current using high range ammeter
B) It helps in measuring high current using low range ammeter
C) It helps in measuring high voltage using high range voltmeter
D) It helps in measuring low voltage using high range ammeter

... Answer is B)
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49. What is the angle between (in degrees) the planes of two moving coils of a dynamometer type 3-phase factor meter ?

A) 0
B) 60
C) 90
D) 120

... Answer is D)
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50. What is the reading (in kW) of both the wattmeter, when measuring the power of a three-phase three wire system having an input of 5 kW and power factor of 0.866 ?

A) 5, 0
B) 3.33, 1.67
C) 2.5, 2.5
D) 1, 4

... Answer is B)
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51. Commutator in DC generator is used for ?

A) collection of current
B) reduce losses
C) increase efficiency
D) convert AC armature current in DC

... Answer is D)
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52. Tappings of a transformer are provided ?

A) at the phase end of lv side
B) at the phase end of hv side hv
C) at the neutral side end of hv side
D) at the middle of hv side

... Answer is D)
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53. DC machine winding are ?

A) full pitched
B) short pitched
C) either of these
D) none of these

... Answer is C)
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54. The armature winding is connected to the external power source through ?

A) commutator system
B) brush system
C) commutator brush system
D) none of these

... Answer is C)
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55. The emf induced in the dc generator armature winding is dc ?

A) AC
B) DC
C) AC & DC
D) None of these

... Answer is A)
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56. In an Auto transformer a part of energy transfer is through ?

A) convection process
B) conduction process
C) induction process
D) radiation process

... Answer is #)
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57. Voltage regulation of transformer is given by ?

A) (E2 –V2 )/V2
B) (E2 – V2 )/E2
C) (V2 – E2 )/E2
D) (V2 – E2 )/V2

... Answer is #)
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58. Which is the only transformer whose primary and secondary are connected to each other electrically ?

A) Shielded Winding transformer
B) Insulating transformer
C) Auto transformer
D) Isolating transformer

... Answer is C)
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59. In a 3-phase induction motor a balanced three phase supply is with electrical angle separation ?

A) 30o
B) 60o
C) 90o
D) 120o

... Answer is D)
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60. The slip of induction motor 0.04 and frequency of motor 60 Hz. Hence, the rotor current frequency ?

A) 24 kHz
B) 24 Hz
C) 2.4 Hz
D) 60 Hz

... Answer is C)
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61. Which single phase motor would you select for a tape recorder ?

A) Reluctance motor
B) Hysteresis motor
C) Synchronous motor
D) Universal motor

... Answer is B)
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62. The direction of rotation of an hysteresis motor is determined by ?

A) interchanging the supply
B) position of shaded pole with respect to main pole
C) retentivity of the rotor material
D) none of these

... Answer is B)
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63. In a capacitor start and run motors the function of the running capacitor in series with the auxiliary winding is to.... ?

A) improve power factor
B) increase overload capacity
C) reduce fluctuations in torque
D) to improve torque

... Answer is #)
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64. The purpose of stator winding in the compensated repulsion motor is to ?

A) provide mechanical balance
B) improve power factor and provide better speed regulation
C) prevent hunting in the motor
D) eliminate armature reaction

... Answer is B)
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65. A hysteresis motor works on the principle of ?

A) hysteresis loss
B) magnetisation of rotor
C) eddy current loss
D) electromagnetic induction

... Answer is B)
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66. Torque developed by a single phase induction motor at starting is ?

A) pulsating
B) uniform
C) non-uniform
D) zero

... Answer is A)
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67. What are the advantage of DC transmission system over AC transmission system ?

A) DC system is economical
B) There is no skin effect in DC system
C) Corona limits are highest for DC circuits as compared to AC circuits
D) All options are correct

... Answer is B)
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68. The high voltage line which feeds the substations, distribution transformers represent ?

A) primary transmission
B) secondary distribution
C) primary distribution
D) secondary transmission

... Answer is D)
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69. Which of the following is not a standard transmission voltage ?

A) 132 kV
B) 222 kV
C) 400 kV
D) 750 kV

... Answer is #)
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70. Dielectric strength of rubber is around ?

A) 3 kV/mm
B) 10 kV/mm
C) 30 kV/mm
D) 300 kV/mm

... Answer is C)
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71. The number of conductors in a double circuit transmission line is ?

A) one earth conductor along with four conductors
B) one earth conductor along with six conductors
C) one earth conductor along with seven conductors
D) one earth conductor along with eight conductors

... Answer is B)
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72. The earth conductor carried in high voltage transmission line is ?

A) above the line conductors
B) below the line conductors
C) between the line conductors
D) none of these

... Answer is A)
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73. The type of wiring that is highly suitable for a temporary shed is ?

A) cleat wiring
B) wooden capping and casting wiring
C) lead sheathed wiring
D) conduit wiring

... Answer is A)
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74. To prevent excessive brightness, which type of lighting scheme is used ?

A) direct
B) indirect
C) general
D) local

... Answer is B)
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75. Ohm's law is applicable to ?

A) Constant and Variable Temperatures
B) Variable temperature
C) Constant Temperature
D) Any of the options

... Answer is C)
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76. Most of the fuses operate due to ?

A)induction effect of current
B) magnetic effect of current
C) heating effect of current
D) electrostatic effect of current

... Answer is C)
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77. Pin insulators are normally used up to voltage of about ?

A) 11 KV
B) 33 KV
C) 66 KV
D) 100 KV

... Answer is B)
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78. The core of the transformer is made of ?

A) copper
B) aluminium
C) air
D) laminated sheath

... Answer is D)
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79. . Forced draft fan handling which type of air ?

A) cold air
B) hot air
C) flue gas only
D) fresh air only

... Answer is A)
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80. Who invented the alternating current ?

A) Edison
B) Faraday
C) Maxwell
D) Tesla

... Answer is D)
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81. The function of inert gas in filament lamp is ?

A) increase the illumination
B) decrease the power consumption
C) minimize the effect of evaporation during service
D) decrease the clare

... Answer is C)
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82. In which one of the following is flexible wire is not used ?

A) T.V.
B) Table fan
C) cement factory
D) Table light

... Answer is C)
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83. The gas used in gas filed filament lamp ?

A) Helium
B) Oxygen
C) Nitrogen
D) Ozone

... Answer is C)
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84. The output of Tungston filament lamp depends on ?

A) Size of lamp
B) Size of shell
C) Temperature of filament
D) All options are correct

... Answer is C)
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85. In arc welding the voltage on AC supply system in the range ?

A) 1000-1200 V
B) 400-500 V
C) 200-250 V
D) 70-1000 V

... Answer is #)
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86. Which of the following is not a welding accessory ?

A) Electrode holder
B) Hand screen
C) Cable
D) Gloves

... Answer is C)
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87. The temperature inside a furnace is usually measured by ?

A) Mercury thermometer
B) Optical pyrometer
C)Alcohol thermometer
D) Any of the options is correct

... Answer is B)
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88. In electric resistance welding ?

A) The current required exceeds 100 A
B) The voltage required ranges from 4 to 12 V
C) The amount of power supplied to the weld usually ranges from 60 watts to 8 watts for each sqaure mm of area
D) All options are correct

... Answer is D)
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89. Which of the following is a trivalent ?

A) Boron
B) Aluminium
C) Indium
D) All options are correct

... Answer is D)
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90. Which of the following are immobile ?

A) Electrons
B) Holes
C) Ions
D) None of these

... Answer is C)
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91. . In an RC coupled amilifier, low frequency response is improved with RC ?

A) lower R1
B) higher CC
C) less gain
D) more bias

... Answer is B)
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92. The direction of rotation of a DC shunt motor is reversed by... ?

A) reversing armature connections
B) interchanging the armature and field connection
C) adding resistance to the field circuit
D) reversing supply connections

... Answer is A)
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93. Which of the following is a correct statement about a series motor ?

A) Its field winding consists of thicker wire and less turns
B) It can run easily without load
C) It has an almost constant speed
D) It has poor torque

... Answer is A)
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94. What is the characteristics of an ideal voltage amplifier with respect to the input and output impedance ?

A) Low input and high output impedance
B) High input and low output impedance
C) Low input and low output impedance
D) High input and high output impedance

... Answer is B)
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95. The percentage full load slip in a synchronous motor is ?

A) 0.01
B) 0.005
C) 1
D) zero

... Answer is D)
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96. In synchronous motor the armature current has higher values for ?

A) high excitation only
B) low excitation only
C) both high excitation only and low excitation only
D) None of these

... Answer is C)
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97. An unexcited single phase synchronous motor is called as ?

A) universal motor
B) repulsion motor
C) AC series motor
D) reluctance motor

... Answer is D)
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98. A constant speed motor is ?

A) dc shunt motor
B) synchronous motor
C) induction motor
D) d.c. compound motor

... Answer is B)
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99. In a synchronous motor of the back e.m.f. is approximately equal to the applied voltage, then ?

A) the torque generated is maximum
B) the excitation is said to be hundred percent
C) the excitation is said to be zero percent
D) the motor is said to be fully loaded

... Answer is B)
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100. A synchronous motor can operate at.. ?

A) leading power factor only
B) lagging power factor only
C) unity power factor only
D) lagging, leading and unity power factors

... Answer is D)
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